Of the following, non-existing compound is

Options

A. `PH_4 I`
B. `As_2 O_3`
C. `SbCl_2`
D. `As_2 H_3`

Explanation

To determine which of the following compounds does not exist, we will analyze each compound provided in the question.

### Step 1: Identify the compounds
The compounds given are:
1. Ph4I
2. As2O3
3. SbCl2
4. As2H3

### Step 2: Analyze each compound for existence
1. **Ph4I**: This compound is known as tetraphenyl iodide. It exists as a stable compound.

2. **As2O3**: This is arsenic trioxide, which is a well-known compound of arsenic. It exists and is commonly encountered in chemistry.

3. **SbCl2**: This compound would imply antimony in a +2 oxidation state. However, antimony (Sb) typically exhibits +3 or +5 oxidation states due to its position in group 15 of the periodic table. Therefore, SbCl2 does not exist.

4. **As2H3**: This compound is known as diarsine. It exists as a chemical compound.

### Step 3: Conclusion
Upon analyzing each compound, we find that the compound that does not exist is **SbCl2**.

### Final Answer
The non-existing compound is **SbCl2**.

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